The present invention relates power tools and, more particularly, to rotary tools. The invention is particularly directed to a tool releasing mechanism for rotary power tools such as rotary tools, routers, and die grinders.
Rotary devices are used for numerous tasks by carpenters, artists and do-it-yourselfers. Rotary devices are ideal for cutting, cleaning, engraving, sanding, sharpening and other applications. Rotary devices are utilized in hobbies, woodwork and numerous tasks, both commercially and residential. Ordinarily, rotary devices include a collet device to retain a tool within the device. The tools usually include cylindrical shafts with a desired diameter. The collets ordinarily frictionally grab the shafts to retain the tools within the rotary device. Ordinarily, the collet has a threaded sleeve which exerts a radial force onto the shaft as it is rotated to tighten down the tool within the device.
In order for the user to change tools in the rotary device, he must rotate the collet sleeve with a wrench while locking the spindle against rotation to loosen it and then remove the tool from the collet. To change to an additional tool, the user must place the tool in the collet and rotate the sleeve with a wrench while locking the spindle against rotation which, in turn, tightens the collet device. This process is time consuming and requires a significant amount of user interaction. Thus, it would be desirable to have a collet which quickly enables removal and retention of the tool. Also, the releasable collet should be easily manipulated by the user requiring a minimum amount of user interaction.
The present invention provides the art with a quick release tool holder which is easily manipulated by the user. The present invention provides a rotatable device which enables quick removal and retention of tools having cylindrical shanks. The present invention provides retention members which solely retain the tools within the rotary device.
In accordance with a first aspect of the invention, a releasable tool holder comprises a spindle having two ends. One of the ends is adapted to secure the spindle to the rotary device. The other end includes a bore to receive a tool. A mechanism to retain and release the tool from the spindle is coupled with the spindle adjacent the bore end. The mechanism comprises at least two unlike retention members to apply a force on the tool in the bore to retain the tool within the bore. A sleeve surrounds a portion of the spindle and the at least two retention members. The sleeve includes a common surface in contact with the at least two retention members to apply a force on the two retention members. The surface contacts the retention member and rolls to a force equilibrium. Thus, the retention member exerts tremendous force on the tool against the surface which maintains the tool in the bore. As the surface moves with respect to the retention member, the force lessens, which enables the tool to be removed from the bore. A biasing member maintains the sleeve in a retention position on the spindle. Preferably, the sleeve common surface is tapered along the spindle axis. A second biasing member may be associated with at least one retention member to register the retention member on the spindle. One of the retention members is a ball while the other is a non-circular elliptical tapered roller. Also, the ball may be a pair of balls.
In accordance with a second aspect of the invention, a rotary device comprises a housing with a motor to provide rotary movement. A power source, either an AC or a DC source, is coupled with the motor. A spindle is coupled with the motor. An activation member is included to energize the motor. A releasable tool is coupled with the spindle. One of the spindle ends is adapted to secure the spindle to the rotary device. The other end includes a bore to receive a tool. A mechanism to retain and release the tool from the spindle is coupled with the spindle adjacent the bore end. The mechanism comprises at least two unlike retention members to apply a force on the tool in the bore to retain the tool within the bore. A sleeve surrounds a portion of the spindle and the at least two retention members. The sleeve includes a common surface in contact with the at least two retention members to apply a force on the two retention members. The surface contacts the retention member and rolls to a force equilibrium. Thus, the retention member exerts tremendous force on the tool against the surface which maintains the tool in the bore. As the surface moves with respect to the retention member, the force lessens, which enables the tool to be removed from the bore. A biasing member maintains the sleeve in a retention position on the spindle. Preferably, the sleeve common surface is tapered along the spindle axis. A second biasing member may be associated with at least one retention member to register the retention member on the spindle. One of the retention members is a ball while the other is a non-circular elliptical tapered roller. Also, the ball may be a pair of balls.
In accordance with a third aspect of the invention, a releasable tool comprises a spindle having two ends. One end is adapted to secure the spindle with a rotary device. The other end includes a bore to receive a tool. A mechanism to retain and release the tool from the spindle is coupled with the spindle adjacent the bore end. The mechanism includes three retention members, a ball and two non-circular elliptical tapered rollers, to apply force on the tool in the bore to retain the tool in the bore. A sleeve surrounds a portion of the spindle and the three retention members. The sleeve includes a common surface tapered along the spindle axis in contact with each of the three retention members. The tapered surface contacts each of the three retention members and rolls to a force equilibrium. The retention members exert a tremendous force on the tool against the tapered surface which maintains the tool in the bore. As the tapered surface moves with respect to the three retention members, the force lessens, which enables the tool to be removed from the bore. A pair of springs are also included. One spring maintains the sleeve in a retention position on the spindle. The other spring, which may include a squared end, registers the ball on the spindle.
In accordance with a fourth aspect of the invention, a releasable tool holder comprises a spindle having two ends. One of the ends is adapted to secure the spindle to the rotary device. The other end includes a bore to receive a tool. A mechanism to retain and release the tool from the spindle is coupled with the spindle adjacent the bore end. The mechanism comprises at least one retention member to apply a force on the tool in the bore to retain the tool within the bore. A sleeve surrounds a portion of the spindle and the at least one retention member. The sleeve includes a surface in contact with the at least one retention member to apply a force on the retention member. The surface contacts the retention member and rolls to a force equilibrium. Thus, the retention member exerts tremendous force on the tool against the surface which maintains the tool in the bore. As the surface moves with respect to the retention member, the force lessens, which enables the tool to be removed from the bore. A biasing member maintains the sleeve in a retention position on the spindle. Preferably, the sleeve surface is tapered along the spindle axis. The sleeve surface may be arcuate with respect to the circumferential direction with a radius larger than the radius of the retention member. The retention members rotate to slightly back drive the sleeve until the arcuate surface frictionally pinches the retention members between the sleeve and tool to stop rotation of the retention members to provide a self-locking feature which prevents the retention members from further back driving the sleeve. A second biasing member may be associated with the at least one retention member to register the retention member on the spindle and to each other. The bottom of the spindle bore may be angled with respect to the spindle axis to center the tool in the bore. An O-ring seal may be positioned in the bore to prohibit contamination from entering the bore. Also, an additional sleeve may be positioned inside the bore to enable retention of smaller diameter tools as well as to reduce marking or abrading of the shank.
In accordance with a fifth aspect of the invention, a rotary device comprises a housing with a motor to provide rotary movement. A power source, either an AC or a DC source, is coupled with the motor. A spindle is coupled with the motor. An activation member is included to energize the motor. A releasable tool is coupled with the spindle. One of the spindle ends is adapted to secure the spindle to the rotary device. The other end includes a bore to receive a tool. A mechanism to retain and release the tool from the spindle is coupled with the spindle adjacent the bore end. The mechanism comprises at least one retention member to apply a force on the tool in the bore to retain the tool within the bore. A sleeve surrounds a portion of the spindle and the at least one retention member. The sleeve includes a surface in contact with the at least one retention member to apply a force on the retention member. The surface contacts the retention member and rolls to a force equilibrium. Thus, the retention member exerts tremendous force on the tool against the surface which maintains the tool in the bore. As the surface moves with respect to the retention member, the force lessens, which enables the tool to be removed from the bore. A biasing member maintains the sleeve in a retention position on the spindle. Preferably, the sleeve surface is tapered along the spindle axis. The sleeve surface may be arcuate with respect to the circumferential direction with a radius larger than the radius of the retention member. The retention members rotate to slightly back drive the sleeve until the arcuate surface frictionally pinches the retention members between the sleeve and tool to stop rotation of the retention members to provide a self-locking feature which prevents the retention members from further back driving the sleeve. A second biasing member may be associated with the at least one retention member to register the retention member on the spindle and to each other. The bottom of the spindle bore may be angled with respect to the spindle axis to center the tool in the bore. An O-ring seal may be positioned in the bore to contact the shaft to prohibit contamination from entering the bore. Also, an additional sleeve may be positioned inside the bore to enable retention of smaller diameter tools as well as to reduce marking or abrading of the shank.
In accordance with a sixth aspect of the invention, a releasable tool comprises a spindle having two ends. One end is adapted to secure the spindle with a rotary device. The other end includes a bore to receive a tool. A mechanism to retain and release the tool from the spindle is coupled with the spindle adjacent the bore end. The mechanism includes three balls to apply force on the tool in the bore to retain the tool in the bore. A sleeve surrounds a portion of the spindle and the three balls. The sleeve includes a surface tapered along the spindle axis in contact with each of the three balls. The tapered surfaces contact each of the three balls and rolls to a force equilibrium. The balls exert a tremendous force on the tool against the tapered surface which maintains the tool in the bore. As the tapered surface moves with respect to the retention member, the force lessens, which enables the tool to be removed from the bore. A pair of springs are also included. One spring maintains the sleeve in a retention position on the spindle. The other spring, which includes a squared end, registers the balls on the spindle. The tapered surfaces may be arcuate in a circumferential direction and have a radius larger than the balls. The retention members rotate to slightly back drive the sleeve until the arcuate surface frictionally pinches the retention members between the sleeve and tool to stop rotation of the retention members to provide a self-locking feature which prevents the retention members from further back driving the sleeve. Also, the bottom of the spindle bore may be angled with respect to the axis of the bore to center the tool in the bore. A sleeve may be positioned in the bore to retain smaller diameter shafts in the bore. Also, the sleeve may be used to protect the shafts from marking, abrading or the like. The sleeve may be a split sleeve with recesses on its outer periphery. Further, an O-ring may be positioned in the bore to contact the tool shaft to prohibit contamination from entering the bore.
Other objects, features and advantages of the present invention will become more fully apparent from the following detailed description of the preferred embodiment and the accompanying drawings.